Soderling, a top-five player when he departed but now unranked, continues to draw inspiration from players such as Tommy Haas of Germany, who came back from multiple injuries and has been playing some of his best tennis at age 35.

"If I don't give it a try I think I will regret it when I'm getting older," said the 28-year-old Soderling. "It's easier to retire and say at least I gave it a try."

With the French Openbeginning Sunday, attention as usual has turned to Nadal.

"Obviously every time he gets to the French he's playing his best tennis," Soderling said.

Of course, Soderling also made his mark in Paris, notably as his personal streak-busting house.

Five years ago, he shocked Nadal in the fourth round on the way to his first major final. He followed up by snapping Roger Federer's record of 23 consecutive Grand Slam semifinals by beating him in the 2010 quarterfinals en route to another runner-up showing.

Nadal got his revenge in the 2010 final, and Federer beat Soderling to win his sole French Open title the year before.

Though Nadal's loss in 2009 remains one of the sport's biggest upsets in recent history, Soderling only remembers the very end of his 6-2, 6-7 (2-7), 6-4, 7-6 (7-2) victory.

"I think I was up 6-1 or 6-2 in the tiebreaker and I thought to myself, 'Now I have a really big chance,' " he said.

He does not recall it as his best effort — not even close.

"It was a good match from my side but I think I played many matches where I played way better tennis," he said.

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Like it or not, that tectonic win remains etched in the public consciousness as his defining moment. It does not occupy the same level of real estate in Soderling's head.

"Of course I had some of my biggest success in Paris in the French Open," he explained. "I beat Nadal in 2009, which was great. ... But I think I'm even more proud of what I did in 2010 when I defended my runner-up and beat Roger in the quarters. It's one thing to reach a Grand Slam final, but to do two in a row makes me really proud."

Soderling had been a mainstay in the top 10 for more than a year when he started to feel below par in the spring of 2011. He played one event after Wimbledon before taking a break to deal with his condition.

Monoucleosis, an energy-sapping viral illness, can be mild or severe and has stricken a number of players from Roger Federer and Andy Roddick to Christina McHale and Mario Ancic.

Like the now-retired Ancic, Soderling has struggled to overcome it.

"It's different week to week," he said of his energy level. "Some weeks I play a little bit more, others not so much. It's hard to put up a training schedule. I have to wake up in the morning and see how I feel from there."

He can hit for 30-40 minutes but must be cautious not to overdo it. He has consulted many doctors. None can provide concrete answers about how to move past the unpredictable disease.

"That of course is a little bit frustrating," said the sometimes fiery Soderling. "But at least you learn to listen to your body."

Robin Soderling of Sweden defeats Roger Federer in the quarterfinals of the French Open on June 1, 2010.(Photo: Patrick Kovarik, AFP/Getty Images)

He and longtime partner Jenni Mostrom became first-time parents seven months ago when they welcomed daughter Olivia into their lives.

The new father lives a busy but quiet life. He is focused on his family and his eventual return to a pro career that saw him reach a high ranking of No. 4 and earn more than $10 million in prize money.

"I have stuff to do all day long but I'm taking it slow and my main focus is getting back to the tennis," he said.

Though Nadal beat Novak Djokovic last year to eclipse Bjorn Borg's then-record of six French Open titles, Soderling isn't willing to concede the Spaniard's superiority over his fellow Swede.

"It's different eras," he said of inevitable comparisons between the two greatest male clay-courters of the Open era. "It's almost impossible to say. Borg was a great player. Nadal is also a great player. They are equally good I think."

At 6-4 with flat, penetrating groundstrokes that made a distinctly percussive sound coming off his racket, Soderling was able to take the initiative against Nadal in a way few players have been able to duplicate.

Sodering admires Nadal for his physical stamina, but he said he also has a psychological advantage over his opponents before they walk on the court.

"He's so strong and everybody knows it," he said.

Soderling rarely carried that kind of mental baggage into compeition, which is why he beat so many top players. Who can forget the Swede mimicking Nadal by tugging at the back of his shorts during a testy loss at Wimbledon in 2007?

Still, he has great respect for Nadal, whose undying effort until the final point creates a constant feeling of uncertainty.

"It's a little bit different with Rafa," he said. "If you're up a set and leading you can have this feeling, 'OK I'm probably going to win this match, just keep it up and I will win.' You never get this feeling against Nadal. Whatever the score is he will always give 100 percent and that is really tough for his opponent."

At 52-1 in Paris, Nadal has earned his swagger. But Sodering can only chuckle that the 11-time major winner never admits to being a favorite, even on clay.

"I think he sees himself as the favorite for sure inside," said Soderling, who called Nadal's protestations to the contrary a pressure-easing ploy.

Soderling doesn't see Nadal's dominance as detrimental because he is "doing something we probably will not see for many, many years." He thinks it's healthy if new players rise up and beat the top men more regularly.

Despite visible annoyance with players whose idiosyncratic routines often made a mockery of the ATP Tour's 25-second time rule between points, Soderling sounded almost sympathetic to the crackdown on time violations this year.

"I don't think any player that takes a lot of time between points does it on purpose," said Soderling, whose pace-of-play tends toward hurried. "Some play fast like Roger. Some taks a little bit more time like Rafa. It's their way of playing but for the sport I think it's good if they can try to speed it up a little bit."

The words echo what Soderling could use, too — a speedy return to the sport.

Robin Soderling, shown here on June 2, 2009, has not played on tour in 22 months because of a debilitating case of mononucleosis. “Of course I had some of my biggest success in Paris in the French Open,” he explained. “I beat Nadal in 2009, which was great…But I think I’m even more proud of what I did in 2010 when I defended my runner-up and beat Roger in the quarters. It’s one thing to reach a Grand Slam final, but to do two in a row makes me really proud.”(Photo: Patrick Kovarik, AFP/Getty Images)